The invention relates generally to a trigger mechanism for optical cable connectors. More particularly, the invention relates a trigger mechanism that is removably attachable to the housing of a connector for engaging a latch on the connector housing and for preventing snagging of the latch.
Various types of connectors have been developed for connecting optical cables to optical system components such as active or passive devices or to other optical cables. Numerous factors influence the design of such connectors, including the diameter and makeup of the optical fiber used in the cable, the environment into which the cable and connector are placed, the space available for connection and the number of connections required in a given location, to name but a few. Four of the optical cable connectors currently in common use have come to be known as SC-type, FC-type, ST-type, and RJ-type connectors.
RJ-type connectors include a cantilevered latch extending at an angle from an outer surface of the latch housing to engage the receptacle into which the connector is placed to secure the connector in place. The distal end of the latch extends generally backwardly (that is, away from the xe2x80x9cfrontxe2x80x9d end of the connector to be inserted into the receptacle and thus xe2x80x9cbackxe2x80x9d in the direction of the cable). Well-known examples of RJ-type connectors include common telephone cord connectors and LC-type optical fiber connectors.
One drawback of RJ-type connectors is that if a cable on which the connector is mounted is pulled backwards after the connector is removed from the receptacle, the latch can get caught, thereby preventing further movement of the cable without potentially damaging or breaking the latch or the associated connector. This may occur, for example, if a cable technician tries to retrieve cables with RJ-type connectors extending through a duct or other remote space in which a large number of cables are present. In case of a snag that can not be reached or loosened by manipulating the cable or cables involved, the cable technician may have no alternative but to pull the snagged cable hard enough to damage or break the connector or other cables. Obviously, such potential situation undesirably puts precision equipment at risk of damage and, at the very least, wastes the time of the cable technician.
Various devices have been proposed to overcome such features of RJ-type connectors. For example, contoured sidewalls have been proposed at the end of the connector and on the latch itself to prevent or reduce snagging, as shown in U.S. Pat. Nos. 4,611,875 and 5,224,186. However, these devices are more difficult to plug in to and unplug from receptacles than are traditional RJ-type connectors due to the presence and locations of the sidewalls.
Also, a second cantilevered element similar to the latch, and often called a xe2x80x9ctrigger,xe2x80x9d has been included as part of RJ-type connector housings. The proximal end of the trigger is at the cable (back) end of the connector and the distal end extends forward to shield the latch in case the cable is pulled backwards. If the cable is pulled backwards, the outer surface of the trigger helps guide the connector in the desired direction while preventing the latch from snagging. When a cable technician squeezes the connector so that the trigger is pivoted down when the connector is in a receptacle, the trigger bottom surface contacts the top surface of the latch to also pivot the latch downward, thereby releasing the connector from the receptacle. One example of an LC connector having such a trigger is disclosed in U.S. Pat. No. 5,638,474.
While such trigger reliably prevents snags and is easy to plug and unplug, the presence of the trigger undesirably lengthens and enlarges the connector housing somewhat as compared to a comparable LC connector without a trigger. Also, the more complicated housing components including the trigger can be more difficult and expensive to mold. Further, to make connectors with triggers, various specific different parts must be manufactured and stocked, thereby incurring greater costs if options and alternatives in design are desired in a family of connectors, especially if some connectors have triggers and some do not. Moreover, both simplex and duplex connector devices may also be more difficult to manufacture and assemble in some cases when triggers are present on the individual connectors.
Accordingly, it is an objective of the present invention to provide a trigger mechanism, an optical cable connector including a trigger mechanism, and a method of assembling an optical cable connector including a trigger mechanism, wherein the component parts of the trigger mechanism and connector are simple, reliable, and economical to manufacture, assemble, and use. Other objectives and advantages of the invention will be apparent from the following description and the attached drawings, or can be learned through practice of the invention.
According to an aspect of the invention, a connector is disclosed for connecting an optical fiber cable to a receptacle, the connector includes a housing subassembly configured for receiving an end of the optical fiber cable and configured to be insertable into the receptacle. The housing subassembly includes a housing and a latch, the latch having a proximal end attached to an outer surface of the housing and a distal end extending from the outer surface. The latch distal end is movable toward and away from the outer surface and configured for engaging the receptacle for releasably securing the housing to the receptacle. A protective member includes a first element and a second element, the first element removably attachable to the housing, the second element having a proximal end attached to the first element and a distal end extending from the first element. The distal end is movable toward and away from the first element for engaging and moving the distal end of the latch to selectably release the housing subassembly from the receptacle. The protective member is configured so as to prevent snagging of the latch upon movement of the optical fiber cable and connector in a direction opposite the end of the optical fiber cable.
Preferably, the first element defines a longitudinally-extending opening configured for receiving the optical fiber cable and permitting the protective member to be longitudinally slid relative to the housing to thereby attach the protective member to the housing. The opening may be configured for permitting the protective member to be radially snapped onto the housing to thereby attach the member to the housing.
Mating attachment elements are preferably disposed on the housing and the first element for releasably attaching and axially securing the first element to the housing. The mating attachment elements may include snap members disposed on the first element and grooves disposed on the housing for receiving the snap members.
Mating alignment elements are preferably disposed on the housing and the first element for rotationally securing the first element relative to the housing. The mating alignment elements may include at least one noncircumferential surface disposed on the housing and at least one corresponding noncircumferential surface disposed on the first element. The noncircumferential surfaces are preferably planar surfaces.
A flexible boot may be disposed around the optical fiber cable and secured to the housing, the flexible boot having a portion disposed within the opening of the first element, the first element and flexible boot being secured together via a radial interference fit. The flexible boot may include an outer surface defining a channel for receiving the first element.
According to another aspect of the invention, a connector is disclosed for connecting an optical fiber cable to a receptacle, the connector including a housing subassembly configured for receiving an end of the optical fiber cable and configured to be insertable into the receptacle. The housing subassembly includes a housing and a latch, the latch having a proximal end attached to an outer surface of the housing and a distal end extending from the outer surface. The latch distal end is movable toward and away from the outer surface and configured for engaging the receptacle for releasably securing the housing to the receptacle. A protective member is attachable to the housing and includes a first element and second element. The second element has a proximal end attached to the first element and a distal end extending from the first element. The distal end is movable toward and away from the first element for engaging and moving the distal end of the latch to selectably release the subassembly from the receptacle. The first element defines a longitudinally-extending opening therethrough and a longitudinally-extending slot in communication with the opening. The slot is configured for permitting the optical fiber cable to be radially inserted into the opening via the slot, and the opening is configured for securing the member to the housing.
According to another aspect of the invention, a method is disclosed for assembling a connector including a housing subassembly having a latch, a protective member having a first element defining a longitudinal slot and an opening and having a second element extending from the first element, and a flexible boot, to an end of a optical fiber cable. The method includes the steps of inserting the end of the optical fiber cable through an opening in the flexible boot; inserting the end of the optical fiber cable through an opening in the housing subassembly; securing the optical fiber cable within the housing subassembly; attaching the flexible boot to the housing subassembly by sliding the flexible boot along the optical fiber cable relative to the housing subassembly; and attaching the protective member to the housing after attaching the flexible boot to thereby operatively align the latch and the second element.
The method may include the substeps of guiding the optical fiber cable through the slot into the opening and sliding the protective member along the optical fiber cable after the guiding substep. The method may alternately include the substep of radially sliding the protective member onto the housing. The method may also include the substeps of guiding attachment elements on the protective member into engagement with attachment elements on the housing subassembly, or of guiding alignment elements on the protective member into alignment with alignment elements on the housing subassembly.
According to another aspect of the invention, a multiplex connector assembly is disclosed for connecting at least two optical fiber cables to a receptacle, the multiplex connector assembly including at least two housing subassemblies, a respective one of the subassemblies being configured for receiving an end of the optical fiber cable and configured to be insertable into the receptacle, a respective one of the subassemblies including a housing and a latch. A respective one of the latches has a proximal end attached to an outer surface of the housing and a distal end extending from the outer surface, the latch distal end being movable toward and away from the outer surface and configured for engaging the receptacle for releasably securing the housing subassembly to the receptacle. A protective member is attachable to the housing and includes a first element and a second element. The second element has a proximal end attached to the first element and a distal end extending from the first element, the distal end being movable toward and away from the first element for engaging and moving the distal end of at least one of the latches to release at least one of the subassemblies from the receptacle. The first element defines at least two longitudinally-extending openings therethrough and at least two longitudinally-extending slots. Each slot is in communication with a respective one of the openings. Each slot is configured for permitting a respective one of the optical fiber cables to be radially inserted into the respective opening via the slot, and each opening is configured for attaching the protective member to a respective housing.
The second element may be configured to simultaneously release both of the latches, or may be configured to selectively release either of the latches. The second element may define at least two triggers disposed on opposite sides of the first element, the triggers being movable in substantially a single plane, the distal ends movable normal to each other.
According to another aspect of the invention, a snag-reducing member is disclosed for an optical fiber cable connector having a housing for insertion into a receptacle and a latch pivotably extending from the housing for securing the housing to the receptacle. The snag-reducing member includes a body configured to radially receive the optical fiber cable and to be axially slid along the optical fiber cable into engagement with the housing, and a trigger having a proximal end attached to the body and a distal end extending from the body. The distal end is movable toward and away from the body for engaging and pivoting the latch to selectably release the connector from the receptacle when the body is engaged with the housing. The distal end extends in a direction so as to reduce snagging of the latch when the optical fiber cable and connector are moved in a direction away from the receptacle.
The body preferably defines an opening therethough and a slot extending along the opening, the opening configured for radially receiving the optical fiber cable via the slot and sliding along the optical fiber cable. The snag-reducing member may be a duplex member for receiving two optical fiber cables each having a connector having a housing, and the body may be configured to radially receive the two optical fiber cables and to be axially slid along the optical fiber cables into engagement with the housings. If so, the body may define two openings therethough and two slots, each slot extending along a respective one of the openings, each opening configured for radially receiving a respective one of the optical fiber cables via the respective slot and sliding along the respective optical fiber cable.